Urinary incontinence (UI) is one of the most common medical problems experienced by postmenopausal women. Incontinence is a symptom-not a disease. The symptoms result typically from aging and childbirth which causes the re-orientation of urethra relative to the bladder neck resulting in reduced sphincter function. There are several forms of incontinence: stress urinary incontinence (SUI) is caused by stress or coughing; urge urinary incontinence (UUI) is associated with a sudden uncontrollable urge to urinate; overflow incontinence (OI) occurs when the bladder is distended; reflex incontinence (RI) is caused by abnormal spinal cord signals. Over 75% of patients suffering from incontinence fall into the stress (SUI) category; about 20% of the affected population suffer from urge incontinence UUI. Absorbent devices are widely used as a palliative treatment for all categories of UI.
Several surgical approaches are utilized to correct incontinence by elevating and supporting the patient's bladder neck junction. In a Burch suprapubic urethropexy, the bladder neck typically is suspended from the Cooper's ligament thus restoring the sphincter's ability to pinch off urine flow. There are other transvaginal surgical approaches that are termed "sling" techniques that alter the orientation of urethra or mid-urethra relative to the bladder to help restore sphincter function.
Other therapeutic options being investigated relate to bulking agents that are injected into the region around the urethra to increase extraluminal pressure on the weakened sphincter region. For example, Contigen.RTM. (manufactured by Collagen Corporation, Palo Alto, Calif. is a cytoscopically insertable implant material made largely of collagen. Collagen is a fiber found naturally in the body and nonantigenic and biocompatible. Contigen treatments typically are short-lived with as many as 20% of the patients needing retreatment after 9 months due to absorption of the collagen. Other injectable materials are being investigated such as a combination of 50% dextranomer microspheres and 50% sodium hyaluronate. For such injectable materials to succeed in augmenting sphincter function in the long-term, studies will have to confirm that the materials are not autobiodegradable from either enzymic or immune responses.
Thus, there is a need for improved surgical and non-surgical instruments and techniques for treating urinary incontinence. Preferably, such improved techniques would be non-surgical. It further would be preferable if such improved techniques would be non-invasive--i.e., not requiring injections of implantable material into the patient's body.